<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Symbol</title>
</head>

<body>
    <script>
        //创建Symbol
        let s = Symbol();
        // console.log(s, typeof a);
        let s2 = Symbol('尚硅谷');
        let s3 = Symbol('尚硅谷');
        console.log(s2 == s3);

        //Symbol.for 创建
        let s4 = Symbol.for('尚硅谷');
        let s5 = Symbol.for('尚硅谷');
        console.log(s4 === s5);

        //不能与其他数据进行运算
        // let result = s + 100;
        // let result = s > 100;
        // let result = s + s;


        //USONB you are so niubility    你真牛B
        // u undefined
        // s string Symbol
        // o object
        // n null number
        // b boolean




    </script>



</body>

</html>